<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" type="text/css" href="1.css" />
</head>
<body>

    <div style="border: 1px solid red">第一个div</div>
    <span style="border: 2px solid greenyellow">第一个span</span>

</body>
</html>